Abstract: A pressure responsive driver couples a reciprocating motor output to a reciprocable piston of a double-acting pump. In one embodiment, the driver comprises a single spring and in another a pair of springs, which transfer reciprocation forces of the motor output to the piston to reciprocate the piston through its pumping strokes. The spring(s) transfers the entirety of the reciprocation forces of the motor output to the piston until a selected outlet pressure from the pump is reached, whereupon the spring(s) compresses to absorb cranking forces and limit maximum pump outlet pressure to about the selected pressure. The reciprocating motion of the motor output is divided between the spring(s) and piston, such that the extent of flexure of the spring(s) is inversely proportional to movement of the piston, whereby the spring(s) takes up any motion of the motor output not used to move the piston.

Abstract: A flushable manifold for diaphragm protected components of a pressure transducer for sensing a flow of fluid comprises a housing having a recess therein and a diaphragm of flexible material over and closing the recess. Inlet and outlet passages communicate with the recess adjacent to and on opposite sides of its periphery, such that fluid introduced at the inlet flows through the manifold to the outlet, with the presence of fluid pressure within the manifold being detected in response to outward deflection of the diaphragm. To facilitate cleaning the manifold of fluid of one type in preparation for receiving fluid of another, one or more channels are formed in the housing within the recess in communication with the inlet and extend toward peripheral side areas of the recess to direct flushing media introduced at the inlet across all of the surfaces of the manifold and to the outlet to thoroughly clean the same.

Abstract: A color change valve structure for rotary head electrostatic spray coating systems, of the type to which a rapid rotation is imparted to a rotary spray head and coating material directed through an orifice against the head for discharge from a peripheral edge of the head in a spray, is characterized by coating material and dump valves behind the head in close proximity with the orifice. The coating material valve controls a flow of coating material from a supply line to the orifice, and the dump valve is operable to establish a passage from the supply line, through the material valve and to a dump outlet. To purge the system of coating material of one color in preparation for spraying material of another, the material valve is closed, the dump valve is opened and a flow of flushing media is established through the supply line, whereby the flushing media cleanses the supply line and material valve.

Abstract: A safety cover for rotary head electrostatic spray coating systems, of the type to which a rapid rotation is imparted to a rotary spray head and a jet of coating material to be sprayed directed thereagainst for discharge from a peripheral edge of the head in a spray, is characterized by a cover movable between positions over and around the head and remote from the head, and a mechanism for moving the cover. When positioned over the head, the cover protects nearby personnel against accidental injury resulting from contact with the rapidly rotating head, and at the same time serves as a receptacle for receiving and containing solvent and residual coating material discharged from the head when the same is cleaned, as for example during color changes when coating materials of different colors are sprayed.